sha1_name: parse less while finding common prefix
[git/git.git] / sha1_name.c
CommitLineData
9938af6a 1#include "cache.h"
b2141fc1 2#include "config.h"
5385f52d 3#include "tag.h"
9938af6a 4#include "commit.h"
5385f52d
JH
5#include "tree.h"
6#include "blob.h"
f3ab49db 7#include "tree-walk.h"
d556fae2 8#include "refs.h"
28fb8438 9#include "remote.h"
dbe44faa 10#include "dir.h"
fad6b9e5 11#include "sha1-array.h"
0317f455 12#include "packfile.h"
9938af6a 13
e82caf38 14static int get_oid_oneline(const char *, struct object_id *, struct commit_list *);
32574b68 15
d2b7d9c7 16typedef int (*disambiguate_hint_fn)(const struct object_id *, void *);
a78fafe7
JH
17
18struct disambiguate_state {
0016043b 19 int len; /* length of prefix in hex chars */
dc01505f 20 char hex_pfx[GIT_MAX_HEXSZ + 1];
d2ee1185 21 struct object_id bin_pfx;
0016043b 22
a78fafe7
JH
23 disambiguate_hint_fn fn;
24 void *cb_data;
d2ee1185 25 struct object_id candidate;
a78fafe7
JH
26 unsigned candidate_exists:1;
27 unsigned candidate_checked:1;
28 unsigned candidate_ok:1;
29 unsigned disambiguate_fn_used:1;
30 unsigned ambiguous:1;
957d7406 31 unsigned always_call_fn:1;
a78fafe7
JH
32};
33
d2b7d9c7 34static void update_candidates(struct disambiguate_state *ds, const struct object_id *current)
a78fafe7 35{
957d7406
JH
36 if (ds->always_call_fn) {
37 ds->ambiguous = ds->fn(current, ds->cb_data) ? 1 : 0;
38 return;
39 }
a78fafe7
JH
40 if (!ds->candidate_exists) {
41 /* this is the first candidate */
d2b7d9c7 42 oidcpy(&ds->candidate, current);
a78fafe7
JH
43 ds->candidate_exists = 1;
44 return;
d2b7d9c7 45 } else if (!oidcmp(&ds->candidate, current)) {
a78fafe7
JH
46 /* the same as what we already have seen */
47 return;
48 }
49
50 if (!ds->fn) {
51 /* cannot disambiguate between ds->candidate and current */
52 ds->ambiguous = 1;
53 return;
54 }
55
56 if (!ds->candidate_checked) {
d2b7d9c7 57 ds->candidate_ok = ds->fn(&ds->candidate, ds->cb_data);
a78fafe7
JH
58 ds->disambiguate_fn_used = 1;
59 ds->candidate_checked = 1;
60 }
61
62 if (!ds->candidate_ok) {
749f763d 63 /* discard the candidate; we know it does not satisfy fn */
d2b7d9c7 64 oidcpy(&ds->candidate, current);
a78fafe7
JH
65 ds->candidate_checked = 0;
66 return;
67 }
68
69 /* if we reach this point, we know ds->candidate satisfies fn */
70 if (ds->fn(current, ds->cb_data)) {
71 /*
72 * if both current and candidate satisfy fn, we cannot
73 * disambiguate.
74 */
75 ds->candidate_ok = 0;
76 ds->ambiguous = 1;
77 }
78
79 /* otherwise, current can be discarded and candidate is still good */
80}
81
cc817ca3
RS
82static int append_loose_object(const struct object_id *oid, const char *path,
83 void *data)
84{
85 oid_array_append(data, oid);
86 return 0;
87}
88
89static int match_sha(unsigned, const unsigned char *, const unsigned char *);
90
0016043b 91static void find_short_object_filename(struct disambiguate_state *ds)
9938af6a 92{
cc817ca3 93 int subdir_nr = ds->bin_pfx.hash[0];
99a19b43 94 struct alternate_object_database *alt;
99a19b43
JH
95 static struct alternate_object_database *fakeent;
96
97 if (!fakeent) {
274ac009
JH
98 /*
99 * Create a "fake" alternate object database that
100 * points to our own object database, to make it
101 * easier to get a temporary working space in
102 * alt->name/alt->base while iterating over the
103 * object databases including our own.
104 */
7f0fa2c0 105 fakeent = alloc_alt_odb(get_object_directory());
99a19b43
JH
106 }
107 fakeent->next = alt_odb_list;
9938af6a 108
a78fafe7 109 for (alt = fakeent; alt && !ds->ambiguous; alt = alt->next) {
cc817ca3
RS
110 int pos;
111
112 if (!alt->loose_objects_subdir_seen[subdir_nr]) {
113 struct strbuf *buf = alt_scratch_buf(alt);
cc817ca3
RS
114 for_each_file_in_obj_subdir(subdir_nr, buf,
115 append_loose_object,
116 NULL, NULL,
117 &alt->loose_objects_cache);
118 alt->loose_objects_subdir_seen[subdir_nr] = 1;
119 }
a78fafe7 120
cc817ca3
RS
121 pos = oid_array_lookup(&alt->loose_objects_cache, &ds->bin_pfx);
122 if (pos < 0)
123 pos = -1 - pos;
124 while (!ds->ambiguous && pos < alt->loose_objects_cache.nr) {
125 const struct object_id *oid;
126 oid = alt->loose_objects_cache.oid + pos;
127 if (!match_sha(ds->len, ds->bin_pfx.hash, oid->hash))
128 break;
129 update_candidates(ds, oid);
130 pos++;
9938af6a 131 }
9938af6a 132 }
9938af6a
JH
133}
134
135static int match_sha(unsigned len, const unsigned char *a, const unsigned char *b)
136{
137 do {
138 if (*a != *b)
139 return 0;
140 a++;
141 b++;
142 len -= 2;
143 } while (len > 1);
144 if (len)
145 if ((*a ^ *b) & 0xf0)
146 return 0;
147 return 1;
148}
149
0016043b 150static void unique_in_pack(struct packed_git *p,
a78fafe7 151 struct disambiguate_state *ds)
9938af6a 152{
f703e6ea 153 uint32_t num, last, i, first = 0;
d2b7d9c7 154 const struct object_id *current = NULL;
f703e6ea
JH
155
156 open_pack_index(p);
157 num = p->num_objects;
158 last = num;
159 while (first < last) {
160 uint32_t mid = (first + last) / 2;
161 const unsigned char *current;
162 int cmp;
163
164 current = nth_packed_object_sha1(p, mid);
d2ee1185 165 cmp = hashcmp(ds->bin_pfx.hash, current);
f703e6ea
JH
166 if (!cmp) {
167 first = mid;
168 break;
9938af6a 169 }
f703e6ea
JH
170 if (cmp > 0) {
171 first = mid+1;
172 continue;
9938af6a 173 }
f703e6ea
JH
174 last = mid;
175 }
176
177 /*
178 * At this point, "first" is the location of the lowest object
1703f9aa 179 * with an object name that could match "bin_pfx". See if we have
f703e6ea
JH
180 * 0, 1 or more objects that actually match(es).
181 */
a78fafe7 182 for (i = first; i < num && !ds->ambiguous; i++) {
d2b7d9c7 183 struct object_id oid;
184 current = nth_packed_object_oid(&oid, p, i);
185 if (!match_sha(ds->len, ds->bin_pfx.hash, current->hash))
f703e6ea 186 break;
a78fafe7 187 update_candidates(ds, current);
9938af6a 188 }
f703e6ea
JH
189}
190
0016043b 191static void find_short_packed_object(struct disambiguate_state *ds)
9938af6a
JH
192{
193 struct packed_git *p;
194
195 prepare_packed_git();
a78fafe7 196 for (p = packed_git; p && !ds->ambiguous; p = p->next)
0016043b 197 unique_in_pack(p, ds);
99a19b43
JH
198}
199
013f276e
JH
200#define SHORT_NAME_NOT_FOUND (-1)
201#define SHORT_NAME_AMBIGUOUS (-2)
202
a78fafe7 203static int finish_object_disambiguation(struct disambiguate_state *ds,
e82caf38 204 struct object_id *oid)
99a19b43 205{
a78fafe7
JH
206 if (ds->ambiguous)
207 return SHORT_NAME_AMBIGUOUS;
99a19b43 208
a78fafe7 209 if (!ds->candidate_exists)
013f276e 210 return SHORT_NAME_NOT_FOUND;
a78fafe7
JH
211
212 if (!ds->candidate_checked)
213 /*
214 * If this is the only candidate, there is no point
215 * calling the disambiguation hint callback.
216 *
217 * On the other hand, if the current candidate
218 * replaced an earlier candidate that did _not_ pass
219 * the disambiguation hint callback, then we do have
220 * more than one objects that match the short name
221 * given, so we should make sure this one matches;
222 * otherwise, if we discovered this one and the one
223 * that we previously discarded in the reverse order,
224 * we would end up showing different results in the
225 * same repository!
226 */
227 ds->candidate_ok = (!ds->disambiguate_fn_used ||
d2b7d9c7 228 ds->fn(&ds->candidate, ds->cb_data));
a78fafe7
JH
229
230 if (!ds->candidate_ok)
013f276e 231 return SHORT_NAME_AMBIGUOUS;
a78fafe7 232
e82caf38 233 oidcpy(oid, &ds->candidate);
9938af6a
JH
234 return 0;
235}
236
d2b7d9c7 237static int disambiguate_commit_only(const struct object_id *oid, void *cb_data_unused)
aa1dec9e 238{
d2b7d9c7 239 int kind = sha1_object_info(oid->hash, NULL);
aa1dec9e
JH
240 return kind == OBJ_COMMIT;
241}
242
d2b7d9c7 243static int disambiguate_committish_only(const struct object_id *oid, void *cb_data_unused)
e2643617
JH
244{
245 struct object *obj;
246 int kind;
247
d2b7d9c7 248 kind = sha1_object_info(oid->hash, NULL);
e2643617
JH
249 if (kind == OBJ_COMMIT)
250 return 1;
251 if (kind != OBJ_TAG)
99a19b43 252 return 0;
e2643617
JH
253
254 /* We need to do this the hard way... */
c251c83d 255 obj = deref_tag(parse_object(oid), NULL, 0);
e2643617
JH
256 if (obj && obj->type == OBJ_COMMIT)
257 return 1;
9938af6a
JH
258 return 0;
259}
260
d2b7d9c7 261static int disambiguate_tree_only(const struct object_id *oid, void *cb_data_unused)
9938af6a 262{
d2b7d9c7 263 int kind = sha1_object_info(oid->hash, NULL);
daba53ae
JH
264 return kind == OBJ_TREE;
265}
9938af6a 266
d2b7d9c7 267static int disambiguate_treeish_only(const struct object_id *oid, void *cb_data_unused)
daba53ae
JH
268{
269 struct object *obj;
270 int kind;
271
d2b7d9c7 272 kind = sha1_object_info(oid->hash, NULL);
daba53ae
JH
273 if (kind == OBJ_TREE || kind == OBJ_COMMIT)
274 return 1;
275 if (kind != OBJ_TAG)
276 return 0;
277
278 /* We need to do this the hard way... */
c251c83d 279 obj = deref_tag(parse_object(oid), NULL, 0);
daba53ae
JH
280 if (obj && (obj->type == OBJ_TREE || obj->type == OBJ_COMMIT))
281 return 1;
282 return 0;
283}
284
d2b7d9c7 285static int disambiguate_blob_only(const struct object_id *oid, void *cb_data_unused)
daba53ae 286{
d2b7d9c7 287 int kind = sha1_object_info(oid->hash, NULL);
daba53ae
JH
288 return kind == OBJ_BLOB;
289}
290
5b33cb1f
JK
291static disambiguate_hint_fn default_disambiguate_hint;
292
293int set_disambiguate_hint_config(const char *var, const char *value)
294{
295 static const struct {
296 const char *name;
297 disambiguate_hint_fn fn;
298 } hints[] = {
299 { "none", NULL },
300 { "commit", disambiguate_commit_only },
301 { "committish", disambiguate_committish_only },
302 { "tree", disambiguate_tree_only },
303 { "treeish", disambiguate_treeish_only },
304 { "blob", disambiguate_blob_only }
305 };
306 int i;
307
308 if (!value)
309 return config_error_nonbool(var);
310
311 for (i = 0; i < ARRAY_SIZE(hints); i++) {
312 if (!strcasecmp(value, hints[i].name)) {
313 default_disambiguate_hint = hints[i].fn;
314 return 0;
315 }
316 }
317
318 return error("unknown hint type for '%s': %s", var, value);
319}
320
0016043b
JK
321static int init_object_disambiguation(const char *name, int len,
322 struct disambiguate_state *ds)
9938af6a 323{
957d7406 324 int i;
9938af6a 325
0016043b
JK
326 if (len < MINIMUM_ABBREV || len > GIT_SHA1_HEXSZ)
327 return -1;
328
329 memset(ds, 0, sizeof(*ds));
0016043b 330
af61c6e0 331 for (i = 0; i < len ;i++) {
9938af6a
JH
332 unsigned char c = name[i];
333 unsigned char val;
9938af6a
JH
334 if (c >= '0' && c <= '9')
335 val = c - '0';
336 else if (c >= 'a' && c <= 'f')
337 val = c - 'a' + 10;
338 else if (c >= 'A' && c <='F') {
339 val = c - 'A' + 10;
340 c -= 'A' - 'a';
341 }
342 else
343 return -1;
0016043b 344 ds->hex_pfx[i] = c;
9938af6a
JH
345 if (!(i & 1))
346 val <<= 4;
d2ee1185 347 ds->bin_pfx.hash[i >> 1] |= val;
9938af6a 348 }
0016043b
JK
349
350 ds->len = len;
59e4e34f 351 ds->hex_pfx[len] = '\0';
0016043b 352 prepare_alt_odb();
957d7406
JH
353 return 0;
354}
355
1b7ba794 356static int show_ambiguous_object(const struct object_id *oid, void *data)
1ffa26c4
JK
357{
358 const struct disambiguate_state *ds = data;
359 struct strbuf desc = STRBUF_INIT;
360 int type;
361
d2b7d9c7 362
1b7ba794 363 if (ds->fn && !ds->fn(oid, ds->cb_data))
1ffa26c4
JK
364 return 0;
365
1b7ba794 366 type = sha1_object_info(oid->hash, NULL);
1ffa26c4 367 if (type == OBJ_COMMIT) {
bc83266a 368 struct commit *commit = lookup_commit(oid);
1ffa26c4
JK
369 if (commit) {
370 struct pretty_print_context pp = {0};
371 pp.date_mode.type = DATE_SHORT;
372 format_commit_message(commit, " %ad - %s", &desc, &pp);
373 }
374 } else if (type == OBJ_TAG) {
d3101b53 375 struct tag *tag = lookup_tag(oid);
1ffa26c4
JK
376 if (!parse_tag(tag) && tag->tag)
377 strbuf_addf(&desc, " %s", tag->tag);
378 }
379
380 advise(" %s %s%s",
1b7ba794 381 find_unique_abbrev(oid->hash, DEFAULT_ABBREV),
1ffa26c4
JK
382 typename(type) ? typename(type) : "unknown type",
383 desc.buf);
384
385 strbuf_release(&desc);
386 return 0;
387}
388
e82caf38 389static int get_short_oid(const char *name, int len, struct object_id *oid,
957d7406
JH
390 unsigned flags)
391{
392 int status;
957d7406 393 struct disambiguate_state ds;
321c89bf 394 int quietly = !!(flags & GET_OID_QUIETLY);
957d7406 395
0016043b 396 if (init_object_disambiguation(name, len, &ds) < 0)
957d7406 397 return -1;
99a19b43 398
321c89bf 399 if (HAS_MULTI_BITS(flags & GET_OID_DISAMBIGUATORS))
e82caf38 400 die("BUG: multiple get_short_oid disambiguator flags");
259942f5 401
321c89bf 402 if (flags & GET_OID_COMMIT)
aa1dec9e 403 ds.fn = disambiguate_commit_only;
321c89bf 404 else if (flags & GET_OID_COMMITTISH)
e2643617 405 ds.fn = disambiguate_committish_only;
321c89bf 406 else if (flags & GET_OID_TREE)
daba53ae 407 ds.fn = disambiguate_tree_only;
321c89bf 408 else if (flags & GET_OID_TREEISH)
daba53ae 409 ds.fn = disambiguate_treeish_only;
321c89bf 410 else if (flags & GET_OID_BLOB)
daba53ae 411 ds.fn = disambiguate_blob_only;
5b33cb1f
JK
412 else
413 ds.fn = default_disambiguate_hint;
aa1dec9e 414
0016043b
JK
415 find_short_object_filename(&ds);
416 find_short_packed_object(&ds);
e82caf38 417 status = finish_object_disambiguation(&ds, oid);
99a19b43 418
1ffa26c4
JK
419 if (!quietly && (status == SHORT_NAME_AMBIGUOUS)) {
420 error(_("short SHA1 %s is ambiguous"), ds.hex_pfx);
421
422 /*
423 * We may still have ambiguity if we simply saw a series of
424 * candidates that did not satisfy our hint function. In
425 * that case, we still want to show them, so disable the hint
426 * function entirely.
427 */
428 if (!ds.ambiguous)
429 ds.fn = NULL;
430
431 advise(_("The candidates are:"));
432 for_each_abbrev(ds.hex_pfx, show_ambiguous_object, &ds);
433 }
434
013f276e
JH
435 return status;
436}
437
d2b7d9c7 438static int collect_ambiguous(const struct object_id *oid, void *data)
fad6b9e5 439{
910650d2 440 oid_array_append(data, oid);
fad6b9e5
JK
441 return 0;
442}
443
957d7406
JH
444int for_each_abbrev(const char *prefix, each_abbrev_fn fn, void *cb_data)
445{
910650d2 446 struct oid_array collect = OID_ARRAY_INIT;
957d7406 447 struct disambiguate_state ds;
fad6b9e5 448 int ret;
957d7406 449
0016043b 450 if (init_object_disambiguation(prefix, strlen(prefix), &ds) < 0)
957d7406 451 return -1;
957d7406 452
957d7406 453 ds.always_call_fn = 1;
fad6b9e5
JK
454 ds.fn = collect_ambiguous;
455 ds.cb_data = &collect;
0016043b
JK
456 find_short_object_filename(&ds);
457 find_short_packed_object(&ds);
fad6b9e5 458
910650d2 459 ret = oid_array_for_each_unique(&collect, fn, cb_data);
460 oid_array_clear(&collect);
fad6b9e5 461 return ret;
957d7406
JH
462}
463
8e3f52d7
JK
464/*
465 * Return the slot of the most-significant bit set in "val". There are various
466 * ways to do this quickly with fls() or __builtin_clzl(), but speed is
467 * probably not a big deal here.
468 */
469static unsigned msb(unsigned long val)
470{
471 unsigned r = 0;
472 while (val >>= 1)
473 r++;
474 return r;
475}
476
5b20ace6
DS
477struct min_abbrev_data {
478 unsigned int init_len;
479 unsigned int cur_len;
480 char *hex;
481};
482
a42d6fd2
DS
483static inline char get_hex_char_from_oid(const struct object_id *oid,
484 unsigned int pos)
485{
486 static const char hex[] = "0123456789abcdef";
487
488 if ((pos & 1) == 0)
489 return hex[oid->hash[pos >> 1] >> 4];
490 else
491 return hex[oid->hash[pos >> 1] & 0xf];
492}
493
5b20ace6 494static int extend_abbrev_len(const struct object_id *oid, void *cb_data)
013f276e 495{
5b20ace6 496 struct min_abbrev_data *mad = cb_data;
47dd0d59 497
5b20ace6 498 unsigned int i = mad->init_len;
a42d6fd2 499 while (mad->hex[i] && mad->hex[i] == get_hex_char_from_oid(oid, i))
5b20ace6
DS
500 i++;
501
502 if (i < GIT_MAX_RAWSZ && i >= mad->cur_len)
503 mad->cur_len = i + 1;
504
505 return 0;
506}
507
508int find_unique_abbrev_r(char *hex, const unsigned char *sha1, int len)
509{
510 struct disambiguate_state ds;
511 struct min_abbrev_data mad;
512 struct object_id oid_ret;
e6c587c7 513 if (len < 0) {
8e3f52d7
JK
514 unsigned long count = approximate_object_count();
515 /*
516 * Add one because the MSB only tells us the highest bit set,
517 * not including the value of all the _other_ bits (so "15"
518 * is only one off of 2^4, but the MSB is the 3rd bit.
519 */
520 len = msb(count) + 1;
521 /*
522 * We now know we have on the order of 2^len objects, which
523 * expects a collision at 2^(len/2). But we also care about hex
524 * chars, not bits, and there are 4 bits per hex. So all
42c78a21 525 * together we need to divide by 2 and round up.
8e3f52d7 526 */
42c78a21 527 len = DIV_ROUND_UP(len, 2);
8e3f52d7
JK
528 /*
529 * For very small repos, we stick with our regular fallback.
530 */
531 if (len < FALLBACK_DEFAULT_ABBREV)
532 len = FALLBACK_DEFAULT_ABBREV;
e6c587c7 533 }
8e3f52d7 534
af49c6d0 535 sha1_to_hex_r(hex, sha1);
ac53fe86 536 if (len == GIT_SHA1_HEXSZ || !len)
537 return GIT_SHA1_HEXSZ;
5b20ace6
DS
538
539 if (init_object_disambiguation(hex, len, &ds) < 0)
540 return -1;
541
542 mad.init_len = len;
543 mad.cur_len = len;
544 mad.hex = hex;
545
546 ds.fn = extend_abbrev_len;
547 ds.always_call_fn = 1;
548 ds.cb_data = (void *)&mad;
549
550 find_short_object_filename(&ds);
551 find_short_packed_object(&ds);
552 (void)finish_object_disambiguation(&ds, &oid_ret);
553
554 hex[mad.cur_len] = 0;
555 return mad.cur_len;
af49c6d0
JK
556}
557
558const char *find_unique_abbrev(const unsigned char *sha1, int len)
559{
ef2ed501 560 static int bufno;
dc01505f 561 static char hexbuffer[4][GIT_MAX_HEXSZ + 1];
3e98919a
RS
562 char *hex = hexbuffer[bufno];
563 bufno = (bufno + 1) % ARRAY_SIZE(hexbuffer);
af49c6d0 564 find_unique_abbrev_r(hex, sha1, len);
b66fde9a 565 return hex;
9938af6a
JH
566}
567
6677c466 568static int ambiguous_path(const char *path, int len)
af13cdf2
LT
569{
570 int slash = 1;
6677c466 571 int cnt;
af13cdf2 572
6677c466 573 for (cnt = 0; cnt < len; cnt++) {
af13cdf2
LT
574 switch (*path++) {
575 case '\0':
576 break;
577 case '/':
578 if (slash)
579 break;
580 slash = 1;
581 continue;
582 case '.':
583 continue;
584 default:
585 slash = 0;
586 continue;
587 }
c054d64e 588 break;
af13cdf2 589 }
6677c466 590 return slash;
af13cdf2
LT
591}
592
a1ad0eb0
JK
593static inline int at_mark(const char *string, int len,
594 const char **suffix, int nr)
ae0ba8e2 595{
ae0ba8e2
JH
596 int i;
597
a1ad0eb0 598 for (i = 0; i < nr; i++) {
ae0ba8e2
JH
599 int suffix_len = strlen(suffix[i]);
600 if (suffix_len <= len
244ea1b5 601 && !strncasecmp(string, suffix[i], suffix_len))
ae0ba8e2
JH
602 return suffix_len;
603 }
604 return 0;
605}
606
a1ad0eb0
JK
607static inline int upstream_mark(const char *string, int len)
608{
609 const char *suffix[] = { "@{upstream}", "@{u}" };
610 return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
611}
612
adfe5d04
JK
613static inline int push_mark(const char *string, int len)
614{
615 const char *suffix[] = { "@{push}" };
616 return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
617}
618
e82caf38 619static int get_oid_1(const char *name, int len, struct object_id *oid, unsigned lookup_flags);
8cd4249c 620static int interpret_nth_prior_checkout(const char *name, int namelen, struct strbuf *buf);
d18ba221 621
e82caf38 622static int get_oid_basic(const char *str, int len, struct object_id *oid,
c41a87dd 623 unsigned int flags)
e86eb666 624{
eedce784 625 static const char *warn_msg = "refname '%.*s' is ambiguous.";
798c35fc
NTND
626 static const char *object_name_msg = N_(
627 "Git normally never creates a ref that ends with 40 hex characters\n"
628 "because it will be ignored when you just specify 40-hex. These refs\n"
629 "may be created by mistake. For example,\n"
630 "\n"
631 " git checkout -b $br $(git rev-parse ...)\n"
632 "\n"
633 "where \"$br\" is somehow empty and a 40-hex ref is created. Please\n"
634 "examine these refs and maybe delete them. Turn this message off by\n"
8dc84fdc 635 "running \"git config advice.objectNameWarning false\"");
e82caf38 636 struct object_id tmp_oid;
ed378ec7 637 char *real_ref = NULL;
ab2a1a32 638 int refs_found = 0;
128fd54d 639 int at, reflog_len, nth_prior = 0;
9938af6a 640
e82caf38 641 if (len == GIT_SHA1_HEXSZ && !get_oid_hex(str, oid)) {
832cf74c 642 if (warn_ambiguous_refs && warn_on_object_refname_ambiguity) {
e82caf38 643 refs_found = dwim_ref(str, len, tmp_oid.hash, &real_ref);
832cf74c 644 if (refs_found > 0) {
25fba78d
JK
645 warning(warn_msg, len, str);
646 if (advice_object_name_warning)
647 fprintf(stderr, "%s\n", _(object_name_msg));
648 }
649 free(real_ref);
798c35fc 650 }
9938af6a 651 return 0;
798c35fc 652 }
9938af6a 653
d18ba221 654 /* basic@{time or number or -number} format to query ref-log */
694500ed 655 reflog_len = at = 0;
f265458f 656 if (len && str[len-1] == '}') {
e883a057 657 for (at = len-4; at >= 0; at--) {
ab2a1a32 658 if (str[at] == '@' && str[at+1] == '{') {
83d16bc7
RR
659 if (str[at+2] == '-') {
660 if (at != 0)
661 /* @{-N} not at start */
662 return -1;
128fd54d
FC
663 nth_prior = 1;
664 continue;
665 }
adfe5d04
JK
666 if (!upstream_mark(str + at, len - at) &&
667 !push_mark(str + at, len - at)) {
28fb8438
JS
668 reflog_len = (len-1) - (at+2);
669 len = at;
670 }
ab2a1a32
JH
671 break;
672 }
d556fae2
SP
673 }
674 }
675
af13cdf2 676 /* Accept only unambiguous ref paths. */
11cf8801 677 if (len && ambiguous_path(str, len))
af13cdf2
LT
678 return -1;
679
128fd54d 680 if (nth_prior) {
d18ba221 681 struct strbuf buf = STRBUF_INIT;
128fd54d
FC
682 int detached;
683
8cd4249c 684 if (interpret_nth_prior_checkout(str, len, &buf) > 0) {
e82caf38 685 detached = (buf.len == GIT_SHA1_HEXSZ && !get_oid_hex(buf.buf, oid));
128fd54d
FC
686 strbuf_release(&buf);
687 if (detached)
688 return 0;
d18ba221 689 }
128fd54d
FC
690 }
691
692 if (!len && reflog_len)
11cf8801 693 /* allow "@{...}" to mean the current branch reflog */
e82caf38 694 refs_found = dwim_ref("HEAD", 4, oid->hash, &real_ref);
128fd54d 695 else if (reflog_len)
e82caf38 696 refs_found = dwim_log(str, len, oid->hash, &real_ref);
f2eba66d 697 else
e82caf38 698 refs_found = dwim_ref(str, len, oid->hash, &real_ref);
d556fae2
SP
699
700 if (!refs_found)
701 return -1;
702
321c89bf 703 if (warn_ambiguous_refs && !(flags & GET_OID_QUIETLY) &&
798c35fc 704 (refs_found > 1 ||
321c89bf 705 !get_short_oid(str, len, &tmp_oid, GET_OID_QUIETLY)))
eedce784 706 warning(warn_msg, len, str);
d556fae2 707
ab2a1a32 708 if (reflog_len) {
ab2a1a32 709 int nth, i;
dddbad72
JS
710 timestamp_t at_time;
711 timestamp_t co_time;
16d7cc90
JH
712 int co_tz, co_cnt;
713
fe558516 714 /* Is it asking for N-th entry, or approxidate? */
ab2a1a32
JH
715 for (i = nth = 0; 0 <= nth && i < reflog_len; i++) {
716 char ch = str[at+2+i];
717 if ('0' <= ch && ch <= '9')
718 nth = nth * 10 + ch - '0';
719 else
720 nth = -1;
721 }
ea360dd0
SP
722 if (100000000 <= nth) {
723 at_time = nth;
724 nth = -1;
725 } else if (0 <= nth)
ab2a1a32 726 at_time = 0;
861f00e3 727 else {
93cfa7c7 728 int errors = 0;
861f00e3 729 char *tmp = xstrndup(str + at + 2, reflog_len);
93cfa7c7 730 at_time = approxidate_careful(tmp, &errors);
861f00e3 731 free(tmp);
28b35632
JK
732 if (errors) {
733 free(real_ref);
a5e10acb 734 return -1;
28b35632 735 }
861f00e3 736 }
e82caf38 737 if (read_ref_at(real_ref, flags, at_time, nth, oid->hash, NULL,
16d7cc90 738 &co_time, &co_tz, &co_cnt)) {
305ebea0 739 if (!len) {
59556548 740 if (starts_with(real_ref, "refs/heads/")) {
305ebea0
RR
741 str = real_ref + 11;
742 len = strlen(real_ref + 11);
743 } else {
744 /* detached HEAD */
745 str = "HEAD";
746 len = 4;
747 }
748 }
c41a87dd 749 if (at_time) {
321c89bf 750 if (!(flags & GET_OID_QUIETLY)) {
c41a87dd
DA
751 warning("Log for '%.*s' only goes "
752 "back to %s.", len, str,
a5481a6c 753 show_date(co_time, co_tz, DATE_MODE(RFC2822)));
c41a87dd
DA
754 }
755 } else {
321c89bf 756 if (flags & GET_OID_QUIETLY) {
c41a87dd
DA
757 exit(128);
758 }
e6eedc31
JS
759 die("Log for '%.*s' only has %d entries.",
760 len, str, co_cnt);
761 }
16d7cc90 762 }
d556fae2
SP
763 }
764
ed378ec7 765 free(real_ref);
d556fae2 766 return 0;
9938af6a
JH
767}
768
9938af6a 769static int get_parent(const char *name, int len,
e82caf38 770 struct object_id *result, int idx)
9938af6a 771{
1e43ed98 772 struct object_id oid;
321c89bf 773 int ret = get_oid_1(name, len, &oid, GET_OID_COMMITTISH);
9938af6a
JH
774 struct commit *commit;
775 struct commit_list *p;
776
777 if (ret)
778 return ret;
bc83266a 779 commit = lookup_commit_reference(&oid);
9938af6a
JH
780 if (parse_commit(commit))
781 return -1;
782 if (!idx) {
e82caf38 783 oidcpy(result, &commit->object.oid);
9938af6a
JH
784 return 0;
785 }
786 p = commit->parents;
787 while (p) {
788 if (!--idx) {
e82caf38 789 oidcpy(result, &p->item->object.oid);
9938af6a
JH
790 return 0;
791 }
792 p = p->next;
793 }
794 return -1;
795}
796
4f7599ac 797static int get_nth_ancestor(const char *name, int len,
e82caf38 798 struct object_id *result, int generation)
4f7599ac 799{
1e43ed98 800 struct object_id oid;
621ff675
LT
801 struct commit *commit;
802 int ret;
803
321c89bf 804 ret = get_oid_1(name, len, &oid, GET_OID_COMMITTISH);
4f7599ac
JH
805 if (ret)
806 return ret;
bc83266a 807 commit = lookup_commit_reference(&oid);
621ff675
LT
808 if (!commit)
809 return -1;
4f7599ac
JH
810
811 while (generation--) {
621ff675 812 if (parse_commit(commit) || !commit->parents)
4f7599ac 813 return -1;
621ff675 814 commit = commit->parents->item;
4f7599ac 815 }
e82caf38 816 oidcpy(result, &commit->object.oid);
4f7599ac
JH
817 return 0;
818}
819
81776315
JH
820struct object *peel_to_type(const char *name, int namelen,
821 struct object *o, enum object_type expected_type)
822{
823 if (name && !namelen)
824 namelen = strlen(name);
81776315 825 while (1) {
c251c83d 826 if (!o || (!o->parsed && !parse_object(&o->oid)))
81776315 827 return NULL;
a6a3f2cc 828 if (expected_type == OBJ_ANY || o->type == expected_type)
81776315
JH
829 return o;
830 if (o->type == OBJ_TAG)
831 o = ((struct tag*) o)->tagged;
832 else if (o->type == OBJ_COMMIT)
833 o = &(((struct commit *) o)->tree->object);
834 else {
835 if (name)
836 error("%.*s: expected %s type, but the object "
837 "dereferences to %s type",
838 namelen, name, typename(expected_type),
839 typename(o->type));
840 return NULL;
841 }
842 }
843}
844
e82caf38 845static int peel_onion(const char *name, int len, struct object_id *oid,
8a10fea4 846 unsigned lookup_flags)
5385f52d 847{
de37d50d 848 struct object_id outer;
5385f52d 849 const char *sp;
885a86ab 850 unsigned int expected_type = 0;
5385f52d
JH
851 struct object *o;
852
853 /*
854 * "ref^{type}" dereferences ref repeatedly until you cannot
855 * dereference anymore, or you get an object of given type,
856 * whichever comes first. "ref^{}" means just dereference
857 * tags until you get a non-tag. "ref^0" is a shorthand for
858 * "ref^{commit}". "commit^{tree}" could be used to find the
859 * top-level tree of the given commit.
860 */
861 if (len < 4 || name[len-1] != '}')
862 return -1;
863
864 for (sp = name + len - 1; name <= sp; sp--) {
865 int ch = *sp;
866 if (ch == '{' && name < sp && sp[-1] == '^')
867 break;
868 }
869 if (sp <= name)
870 return -1;
871
872 sp++; /* beginning of type name, or closing brace for empty */
59556548 873 if (starts_with(sp, "commit}"))
1974632c 874 expected_type = OBJ_COMMIT;
59556548 875 else if (starts_with(sp, "tag}"))
75aa26d3 876 expected_type = OBJ_TAG;
59556548 877 else if (starts_with(sp, "tree}"))
1974632c 878 expected_type = OBJ_TREE;
59556548 879 else if (starts_with(sp, "blob}"))
1974632c 880 expected_type = OBJ_BLOB;
59556548 881 else if (starts_with(sp, "object}"))
a6a3f2cc 882 expected_type = OBJ_ANY;
5385f52d 883 else if (sp[0] == '}')
1974632c 884 expected_type = OBJ_NONE;
32574b68
NTND
885 else if (sp[0] == '/')
886 expected_type = OBJ_COMMIT;
5385f52d
JH
887 else
888 return -1;
889
321c89bf 890 lookup_flags &= ~GET_OID_DISAMBIGUATORS;
e2643617 891 if (expected_type == OBJ_COMMIT)
321c89bf 892 lookup_flags |= GET_OID_COMMITTISH;
ed1ca602 893 else if (expected_type == OBJ_TREE)
321c89bf 894 lookup_flags |= GET_OID_TREEISH;
e2643617 895
e82caf38 896 if (get_oid_1(name, sp - name - 2, &outer, lookup_flags))
5385f52d
JH
897 return -1;
898
c251c83d 899 o = parse_object(&outer);
5385f52d
JH
900 if (!o)
901 return -1;
885a86ab 902 if (!expected_type) {
9534f40b 903 o = deref_tag(o, name, sp - name - 2);
c251c83d 904 if (!o || (!o->parsed && !parse_object(&o->oid)))
6e1c6c10 905 return -1;
e82caf38 906 oidcpy(oid, &o->oid);
32574b68 907 return 0;
5385f52d 908 }
32574b68
NTND
909
910 /*
911 * At this point, the syntax look correct, so
912 * if we do not get the needed object, we should
913 * barf.
914 */
915 o = peel_to_type(name, len, o, expected_type);
916 if (!o)
81776315 917 return -1;
32574b68 918
e82caf38 919 oidcpy(oid, &o->oid);
32574b68
NTND
920 if (sp[0] == '/') {
921 /* "$commit^{/foo}" */
922 char *prefix;
923 int ret;
924 struct commit_list *list = NULL;
925
81776315 926 /*
4322842a
NTND
927 * $commit^{/}. Some regex implementation may reject.
928 * We don't need regex anyway. '' pattern always matches.
5385f52d 929 */
4322842a 930 if (sp[1] == '}')
81776315 931 return 0;
4322842a 932
32574b68
NTND
933 prefix = xstrndup(sp + 1, name + len - 1 - (sp + 1));
934 commit_list_insert((struct commit *)o, &list);
e82caf38 935 ret = get_oid_oneline(prefix, oid, list);
32574b68
NTND
936 free(prefix);
937 return ret;
5385f52d
JH
938 }
939 return 0;
940}
941
e82caf38 942static int get_describe_name(const char *name, int len, struct object_id *oid)
7dd45e15
JH
943{
944 const char *cp;
321c89bf 945 unsigned flags = GET_OID_QUIETLY | GET_OID_COMMIT;
7dd45e15
JH
946
947 for (cp = name + len - 1; name + 2 <= cp; cp--) {
948 char ch = *cp;
6f75d45b 949 if (!isxdigit(ch)) {
7dd45e15
JH
950 /* We must be looking at g in "SOMETHING-g"
951 * for it to be describe output.
952 */
953 if (ch == 'g' && cp[-1] == '-') {
954 cp++;
955 len -= cp - name;
e82caf38 956 return get_short_oid(cp, len, oid, flags);
7dd45e15
JH
957 }
958 }
959 }
960 return -1;
961}
962
e82caf38 963static int get_oid_1(const char *name, int len, struct object_id *oid, unsigned lookup_flags)
9938af6a 964{
0601dbe1 965 int ret, has_suffix;
4f7599ac 966 const char *cp;
9938af6a 967
621ff675
LT
968 /*
969 * "name~3" is "name^^^", "name~" is "name~1", and "name^" is "name^1".
4f7599ac 970 */
0601dbe1 971 has_suffix = 0;
4f7599ac
JH
972 for (cp = name + len - 1; name <= cp; cp--) {
973 int ch = *cp;
974 if ('0' <= ch && ch <= '9')
975 continue;
0601dbe1
JH
976 if (ch == '~' || ch == '^')
977 has_suffix = ch;
4f7599ac
JH
978 break;
979 }
0601dbe1
JH
980
981 if (has_suffix) {
982 int num = 0;
4f7599ac
JH
983 int len1 = cp - name;
984 cp++;
985 while (cp < name + len)
0601dbe1 986 num = num * 10 + *cp++ - '0';
621ff675
LT
987 if (!num && len1 == len - 1)
988 num = 1;
989 if (has_suffix == '^')
e82caf38 990 return get_parent(name, len1, oid, num);
0601dbe1 991 /* else if (has_suffix == '~') -- goes without saying */
e82caf38 992 return get_nth_ancestor(name, len1, oid, num);
4f7599ac
JH
993 }
994
e82caf38 995 ret = peel_onion(name, len, oid, lookup_flags);
5385f52d
JH
996 if (!ret)
997 return 0;
998
e82caf38 999 ret = get_oid_basic(name, len, oid, lookup_flags);
9938af6a
JH
1000 if (!ret)
1001 return 0;
7dd45e15
JH
1002
1003 /* It could be describe output that is "SOMETHING-gXXXX" */
e82caf38 1004 ret = get_describe_name(name, len, oid);
7dd45e15
JH
1005 if (!ret)
1006 return 0;
1007
e82caf38 1008 return get_short_oid(name, len, oid, lookup_flags);
9938af6a
JH
1009}
1010
f7bff003
JH
1011/*
1012 * This interprets names like ':/Initial revision of "git"' by searching
1013 * through history and returning the first commit whose message starts
3d045897 1014 * the given regular expression.
f7bff003 1015 *
0769854f
WP
1016 * For negative-matching, prefix the pattern-part with '!-', like: ':/!-WIP'.
1017 *
1018 * For a literal '!' character at the beginning of a pattern, you have to repeat
1019 * that, like: ':/!!foo'
1020 *
1021 * For future extension, all other sequences beginning with ':/!' are reserved.
f7bff003 1022 */
208acbfb
NTND
1023
1024/* Remember to update object flag allocation in object.h */
f7bff003
JH
1025#define ONELINE_SEEN (1u<<20)
1026
9c5fe0b8
MH
1027static int handle_one_ref(const char *path, const struct object_id *oid,
1028 int flag, void *cb_data)
28a4d940
JS
1029{
1030 struct commit_list **list = cb_data;
c251c83d 1031 struct object *object = parse_object(oid);
28a4d940
JS
1032 if (!object)
1033 return 0;
affeef12 1034 if (object->type == OBJ_TAG) {
28a4d940 1035 object = deref_tag(object, path, strlen(path));
affeef12
MK
1036 if (!object)
1037 return 0;
1038 }
28a4d940
JS
1039 if (object->type != OBJ_COMMIT)
1040 return 0;
e8d1dfe6 1041 commit_list_insert((struct commit *)object, list);
28a4d940
JS
1042 return 0;
1043}
1044
e82caf38 1045static int get_oid_oneline(const char *prefix, struct object_id *oid,
84baa31b 1046 struct commit_list *list)
28a4d940 1047{
84baa31b 1048 struct commit_list *backup = NULL, *l;
28042dbc 1049 int found = 0;
0769854f 1050 int negative = 0;
57895105 1051 regex_t regex;
28a4d940
JS
1052
1053 if (prefix[0] == '!') {
28a4d940 1054 prefix++;
0769854f
WP
1055
1056 if (prefix[0] == '-') {
1057 prefix++;
1058 negative = 1;
1059 } else if (prefix[0] != '!') {
e6a6a768 1060 return -1;
0769854f 1061 }
28a4d940 1062 }
57895105
LT
1063
1064 if (regcomp(&regex, prefix, REG_EXTENDED))
aac4fac1 1065 return -1;
57895105 1066
84baa31b
NTND
1067 for (l = list; l; l = l->next) {
1068 l->item->object.flags |= ONELINE_SEEN;
28a4d940 1069 commit_list_insert(l->item, &backup);
84baa31b 1070 }
ed8ad7e2 1071 while (list) {
ba41c1c9 1072 const char *p, *buf;
1358e7d6 1073 struct commit *commit;
28042dbc 1074 int matches;
ed8ad7e2
JM
1075
1076 commit = pop_most_recent_commit(&list, ONELINE_SEEN);
c251c83d 1077 if (!parse_object(&commit->object.oid))
283cdbcf 1078 continue;
8597ea3a 1079 buf = get_commit_buffer(commit, NULL);
ba41c1c9 1080 p = strstr(buf, "\n\n");
0769854f 1081 matches = negative ^ (p && !regexec(&regex, p + 2, 0, NULL, 0));
ba41c1c9 1082 unuse_commit_buffer(commit, buf);
28042dbc
JH
1083
1084 if (matches) {
e82caf38 1085 oidcpy(oid, &commit->object.oid);
28042dbc 1086 found = 1;
28a4d940
JS
1087 break;
1088 }
1089 }
57895105 1090 regfree(&regex);
28a4d940
JS
1091 free_commit_list(list);
1092 for (l = backup; l; l = l->next)
1093 clear_commit_marks(l->item, ONELINE_SEEN);
28042dbc
JH
1094 free_commit_list(backup);
1095 return found ? 0 : -1;
28a4d940
JS
1096}
1097
ae5a6c36 1098struct grab_nth_branch_switch_cbdata {
98f85ff4
JH
1099 int remaining;
1100 struct strbuf buf;
ae5a6c36
JH
1101};
1102
9461d272 1103static int grab_nth_branch_switch(struct object_id *ooid, struct object_id *noid,
dddbad72 1104 const char *email, timestamp_t timestamp, int tz,
ae5a6c36
JH
1105 const char *message, void *cb_data)
1106{
1107 struct grab_nth_branch_switch_cbdata *cb = cb_data;
a884d0cb
TR
1108 const char *match = NULL, *target = NULL;
1109 size_t len;
1110
95b567c7 1111 if (skip_prefix(message, "checkout: moving from ", &match))
d7c03c1f 1112 target = strstr(match, " to ");
ae5a6c36 1113
c829774c 1114 if (!match || !target)
ae5a6c36 1115 return 0;
98f85ff4
JH
1116 if (--(cb->remaining) == 0) {
1117 len = target - match;
1118 strbuf_reset(&cb->buf);
1119 strbuf_add(&cb->buf, match, len);
1120 return 1; /* we are done */
1121 }
ae5a6c36
JH
1122 return 0;
1123}
1124
1125/*
ae0ba8e2
JH
1126 * Parse @{-N} syntax, return the number of characters parsed
1127 * if successful; otherwise signal an error with negative value.
ae5a6c36 1128 */
8cd4249c
JK
1129static int interpret_nth_prior_checkout(const char *name, int namelen,
1130 struct strbuf *buf)
ae5a6c36 1131{
c2883e62 1132 long nth;
98f85ff4 1133 int retval;
ae5a6c36 1134 struct grab_nth_branch_switch_cbdata cb;
a884d0cb
TR
1135 const char *brace;
1136 char *num_end;
ae5a6c36 1137
8cd4249c
JK
1138 if (namelen < 4)
1139 return -1;
ae5a6c36
JH
1140 if (name[0] != '@' || name[1] != '{' || name[2] != '-')
1141 return -1;
8cd4249c 1142 brace = memchr(name, '}', namelen);
a884d0cb
TR
1143 if (!brace)
1144 return -1;
98f85ff4 1145 nth = strtol(name + 3, &num_end, 10);
a884d0cb 1146 if (num_end != brace)
ae5a6c36 1147 return -1;
c2883e62
JH
1148 if (nth <= 0)
1149 return -1;
98f85ff4
JH
1150 cb.remaining = nth;
1151 strbuf_init(&cb.buf, 20);
1152
39765e59 1153 retval = 0;
98f85ff4
JH
1154 if (0 < for_each_reflog_ent_reverse("HEAD", grab_nth_branch_switch, &cb)) {
1155 strbuf_reset(buf);
e992d1eb 1156 strbuf_addbuf(buf, &cb.buf);
98f85ff4
JH
1157 retval = brace - name + 1;
1158 }
a884d0cb 1159
98f85ff4 1160 strbuf_release(&cb.buf);
39765e59 1161 return retval;
ae5a6c36
JH
1162}
1163
151b2911 1164int get_oid_mb(const char *name, struct object_id *oid)
619a644d
JH
1165{
1166 struct commit *one, *two;
1167 struct commit_list *mbs;
151b2911 1168 struct object_id oid_tmp;
619a644d
JH
1169 const char *dots;
1170 int st;
1171
1172 dots = strstr(name, "...");
1173 if (!dots)
151b2911 1174 return get_oid(name, oid);
619a644d 1175 if (dots == name)
151b2911 1176 st = get_oid("HEAD", &oid_tmp);
619a644d
JH
1177 else {
1178 struct strbuf sb;
1179 strbuf_init(&sb, dots - name);
1180 strbuf_add(&sb, name, dots - name);
e82caf38 1181 st = get_oid_committish(sb.buf, &oid_tmp);
619a644d
JH
1182 strbuf_release(&sb);
1183 }
1184 if (st)
1185 return st;
bc83266a 1186 one = lookup_commit_reference_gently(&oid_tmp, 0);
619a644d
JH
1187 if (!one)
1188 return -1;
1189
e82caf38 1190 if (get_oid_committish(dots[3] ? (dots + 3) : "HEAD", &oid_tmp))
619a644d 1191 return -1;
bc83266a 1192 two = lookup_commit_reference_gently(&oid_tmp, 0);
619a644d
JH
1193 if (!two)
1194 return -1;
2ce406cc 1195 mbs = get_merge_bases(one, two);
619a644d
JH
1196 if (!mbs || mbs->next)
1197 st = -1;
1198 else {
1199 st = 0;
151b2911 1200 oidcpy(oid, &mbs->item->object.oid);
619a644d
JH
1201 }
1202 free_commit_list(mbs);
1203 return st;
1204}
1205
9ba89f48
FC
1206/* parse @something syntax, when 'something' is not {.*} */
1207static int interpret_empty_at(const char *name, int namelen, int len, struct strbuf *buf)
1208{
1209 const char *next;
1210
1211 if (len || name[1] == '{')
1212 return -1;
1213
1214 /* make sure it's a single @, or @@{.*}, not @foo */
8cd4249c 1215 next = memchr(name + len + 1, '@', namelen - len - 1);
9ba89f48
FC
1216 if (next && next[1] != '{')
1217 return -1;
1218 if (!next)
1219 next = name + namelen;
1220 if (next != name + 1)
1221 return -1;
1222
1223 strbuf_reset(buf);
1224 strbuf_add(buf, "HEAD", 4);
1225 return 1;
1226}
1227
0e9f62da
JK
1228static int reinterpret(const char *name, int namelen, int len,
1229 struct strbuf *buf, unsigned allowed)
7a0a49a7
FC
1230{
1231 /* we have extra data, which might need further processing */
1232 struct strbuf tmp = STRBUF_INIT;
1233 int used = buf->len;
1234 int ret;
1235
1236 strbuf_add(buf, name + len, namelen - len);
0e9f62da 1237 ret = interpret_branch_name(buf->buf, buf->len, &tmp, allowed);
7a0a49a7
FC
1238 /* that data was not interpreted, remove our cruft */
1239 if (ret < 0) {
1240 strbuf_setlen(buf, used);
1241 return len;
1242 }
1243 strbuf_reset(buf);
1244 strbuf_addbuf(buf, &tmp);
1245 strbuf_release(&tmp);
1246 /* tweak for size of {-N} versus expanded ref name */
1247 return ret - used + len;
1248}
1249
a39c14af
JK
1250static void set_shortened_ref(struct strbuf *buf, const char *ref)
1251{
1252 char *s = shorten_unambiguous_ref(ref, 0);
1253 strbuf_reset(buf);
1254 strbuf_addstr(buf, s);
1255 free(s);
1256}
1257
0e9f62da
JK
1258static int branch_interpret_allowed(const char *refname, unsigned allowed)
1259{
1260 if (!allowed)
1261 return 1;
1262
1263 if ((allowed & INTERPRET_BRANCH_LOCAL) &&
1264 starts_with(refname, "refs/heads/"))
1265 return 1;
1266 if ((allowed & INTERPRET_BRANCH_REMOTE) &&
1267 starts_with(refname, "refs/remotes/"))
1268 return 1;
1269
1270 return 0;
1271}
1272
48c58471
JK
1273static int interpret_branch_mark(const char *name, int namelen,
1274 int at, struct strbuf *buf,
1275 int (*get_mark)(const char *, int),
1276 const char *(*get_data)(struct branch *,
0e9f62da
JK
1277 struct strbuf *),
1278 unsigned allowed)
a39c14af
JK
1279{
1280 int len;
48c58471
JK
1281 struct branch *branch;
1282 struct strbuf err = STRBUF_INIT;
1283 const char *value;
a39c14af 1284
48c58471 1285 len = get_mark(name + at, namelen - at);
a39c14af
JK
1286 if (!len)
1287 return -1;
1288
3f6eb30f
JK
1289 if (memchr(name, ':', at))
1290 return -1;
1291
48c58471
JK
1292 if (at) {
1293 char *name_str = xmemdupz(name, at);
1294 branch = branch_get(name_str);
1295 free(name_str);
1296 } else
1297 branch = branch_get(NULL);
1298
1299 value = get_data(branch, &err);
1300 if (!value)
1301 die("%s", err.buf);
1302
0e9f62da
JK
1303 if (!branch_interpret_allowed(value, allowed))
1304 return -1;
1305
48c58471 1306 set_shortened_ref(buf, value);
a39c14af
JK
1307 return len + at;
1308}
1309
0e9f62da
JK
1310int interpret_branch_name(const char *name, int namelen, struct strbuf *buf,
1311 unsigned allowed)
ae0ba8e2 1312{
f278f40f 1313 char *at;
9892d5d4 1314 const char *start;
13228c30 1315 int len;
ae0ba8e2 1316
cf99a761
FC
1317 if (!namelen)
1318 namelen = strlen(name);
1319
0e9f62da
JK
1320 if (!allowed || (allowed & INTERPRET_BRANCH_LOCAL)) {
1321 len = interpret_nth_prior_checkout(name, namelen, buf);
1322 if (!len) {
1323 return len; /* syntax Ok, not enough switches */
1324 } else if (len > 0) {
1325 if (len == namelen)
1326 return len; /* consumed all */
1327 else
1328 return reinterpret(name, namelen, len, buf, allowed);
1329 }
d46a8301
JK
1330 }
1331
9892d5d4
JK
1332 for (start = name;
1333 (at = memchr(start, '@', namelen - (start - name)));
1334 start = at + 1) {
9ba89f48 1335
0e9f62da
JK
1336 if (!allowed || (allowed & INTERPRET_BRANCH_HEAD)) {
1337 len = interpret_empty_at(name, namelen, at - name, buf);
1338 if (len > 0)
1339 return reinterpret(name, namelen, len, buf,
1340 allowed);
1341 }
9ba89f48 1342
48c58471 1343 len = interpret_branch_mark(name, namelen, at - name, buf,
0e9f62da
JK
1344 upstream_mark, branch_get_upstream,
1345 allowed);
9892d5d4
JK
1346 if (len > 0)
1347 return len;
adfe5d04
JK
1348
1349 len = interpret_branch_mark(name, namelen, at - name, buf,
0e9f62da
JK
1350 push_mark, branch_get_push,
1351 allowed);
9892d5d4
JK
1352 if (len > 0)
1353 return len;
bb0dab5d 1354 }
9ba89f48 1355
a39c14af 1356 return -1;
ae0ba8e2
JH
1357}
1358
0e9f62da 1359void strbuf_branchname(struct strbuf *sb, const char *name, unsigned allowed)
6bab74e7
JN
1360{
1361 int len = strlen(name);
0e9f62da 1362 int used = interpret_branch_name(name, len, sb, allowed);
84cf2466 1363
84cf2466
JH
1364 if (used < 0)
1365 used = 0;
1366 strbuf_add(sb, name + used, len - used);
6bab74e7
JN
1367}
1368
1369int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
1370{
7d5c960b 1371 strbuf_branchname(sb, name, INTERPRET_BRANCH_LOCAL);
6bab74e7 1372 if (name[0] == '-')
8d9c5010 1373 return -1;
6bab74e7 1374 strbuf_splice(sb, 0, 0, "refs/heads/", 11);
8d9c5010 1375 return check_refname_format(sb->buf, 0);
6bab74e7
JN
1376}
1377
9938af6a 1378/*
e82caf38 1379 * This is like "get_oid_basic()", except it allows "object ID expressions",
9938af6a
JH
1380 * notably "xyz^" for "parent of xyz"
1381 */
2764fd93 1382int get_oid(const char *name, struct object_id *oid)
1383{
e82caf38 1384 struct object_context unused;
1385 return get_oid_with_context(name, 0, oid, &unused);
2764fd93 1386}
1387
1388
cd74e473 1389/*
a8a5406a 1390 * Many callers know that the user meant to name a commit-ish by
cd74e473
JH
1391 * syntactical positions where the object name appears. Calling this
1392 * function allows the machinery to disambiguate shorter-than-unique
a8a5406a 1393 * abbreviated object names between commit-ish and others.
cd74e473
JH
1394 *
1395 * Note that this does NOT error out when the named object is not a
a8a5406a 1396 * commit-ish. It is merely to give a hint to the disambiguation
cd74e473
JH
1397 * machinery.
1398 */
e82caf38 1399int get_oid_committish(const char *name, struct object_id *oid)
cd74e473
JH
1400{
1401 struct object_context unused;
321c89bf 1402 return get_oid_with_context(name, GET_OID_COMMITTISH,
e82caf38 1403 oid, &unused);
cd74e473
JH
1404}
1405
e82caf38 1406int get_oid_treeish(const char *name, struct object_id *oid)
daba53ae
JH
1407{
1408 struct object_context unused;
321c89bf 1409 return get_oid_with_context(name, GET_OID_TREEISH,
e82caf38 1410 oid, &unused);
daba53ae
JH
1411}
1412
e82caf38 1413int get_oid_commit(const char *name, struct object_id *oid)
daba53ae
JH
1414{
1415 struct object_context unused;
321c89bf 1416 return get_oid_with_context(name, GET_OID_COMMIT,
e82caf38 1417 oid, &unused);
daba53ae
JH
1418}
1419
e82caf38 1420int get_oid_tree(const char *name, struct object_id *oid)
daba53ae
JH
1421{
1422 struct object_context unused;
321c89bf 1423 return get_oid_with_context(name, GET_OID_TREE,
e82caf38 1424 oid, &unused);
daba53ae
JH
1425}
1426
e82caf38 1427int get_oid_blob(const char *name, struct object_id *oid)
daba53ae
JH
1428{
1429 struct object_context unused;
321c89bf 1430 return get_oid_with_context(name, GET_OID_BLOB,
e82caf38 1431 oid, &unused);
a0cd87a5
MK
1432}
1433
009fee47 1434/* Must be called only when object_name:filename doesn't exist. */
e82caf38 1435static void diagnose_invalid_oid_path(const char *prefix,
1436 const char *filename,
1437 const struct object_id *tree_oid,
1438 const char *object_name,
1439 int object_name_len)
009fee47 1440{
e82caf38 1441 struct object_id oid;
009fee47
MM
1442 unsigned mode;
1443
1444 if (!prefix)
1445 prefix = "";
1446
dbe44faa 1447 if (file_exists(filename))
b2981d06
RS
1448 die("Path '%s' exists on disk, but not in '%.*s'.",
1449 filename, object_name_len, object_name);
c7054209 1450 if (is_missing_file_error(errno)) {
b2724c87 1451 char *fullname = xstrfmt("%s%s", prefix, filename);
009fee47 1452
e82caf38 1453 if (!get_tree_entry(tree_oid->hash, fullname,
1454 oid.hash, &mode)) {
009fee47 1455 die("Path '%s' exists, but not '%s'.\n"
b2981d06 1456 "Did you mean '%.*s:%s' aka '%.*s:./%s'?",
009fee47
MM
1457 fullname,
1458 filename,
b2981d06 1459 object_name_len, object_name,
e41d718c 1460 fullname,
b2981d06 1461 object_name_len, object_name,
e41d718c 1462 filename);
009fee47 1463 }
b2981d06
RS
1464 die("Path '%s' does not exist in '%.*s'",
1465 filename, object_name_len, object_name);
009fee47
MM
1466 }
1467}
1468
1469/* Must be called only when :stage:filename doesn't exist. */
1470static void diagnose_invalid_index_path(int stage,
1471 const char *prefix,
1472 const char *filename)
1473{
9c5e6c80 1474 const struct cache_entry *ce;
009fee47
MM
1475 int pos;
1476 unsigned namelen = strlen(filename);
43bb66ae 1477 struct strbuf fullname = STRBUF_INIT;
009fee47
MM
1478
1479 if (!prefix)
1480 prefix = "";
1481
1482 /* Wrong stage number? */
1483 pos = cache_name_pos(filename, namelen);
1484 if (pos < 0)
1485 pos = -pos - 1;
77e8466f
MH
1486 if (pos < active_nr) {
1487 ce = active_cache[pos];
1488 if (ce_namelen(ce) == namelen &&
1489 !memcmp(ce->name, filename, namelen))
1490 die("Path '%s' is in the index, but not at stage %d.\n"
1491 "Did you mean ':%d:%s'?",
1492 filename, stage,
1493 ce_stage(ce), filename);
1494 }
009fee47
MM
1495
1496 /* Confusion between relative and absolute filenames? */
43bb66ae
JK
1497 strbuf_addstr(&fullname, prefix);
1498 strbuf_addstr(&fullname, filename);
1499 pos = cache_name_pos(fullname.buf, fullname.len);
009fee47
MM
1500 if (pos < 0)
1501 pos = -pos - 1;
77e8466f
MH
1502 if (pos < active_nr) {
1503 ce = active_cache[pos];
43bb66ae
JK
1504 if (ce_namelen(ce) == fullname.len &&
1505 !memcmp(ce->name, fullname.buf, fullname.len))
77e8466f 1506 die("Path '%s' is in the index, but not '%s'.\n"
e41d718c 1507 "Did you mean ':%d:%s' aka ':%d:./%s'?",
43bb66ae
JK
1508 fullname.buf, filename,
1509 ce_stage(ce), fullname.buf,
e41d718c 1510 ce_stage(ce), filename);
77e8466f 1511 }
009fee47 1512
dbe44faa 1513 if (file_exists(filename))
009fee47 1514 die("Path '%s' exists on disk, but not in the index.", filename);
c7054209 1515 if (is_missing_file_error(errno))
009fee47
MM
1516 die("Path '%s' does not exist (neither on disk nor in the index).",
1517 filename);
1518
43bb66ae 1519 strbuf_release(&fullname);
009fee47
MM
1520}
1521
1522
979f7929
NTND
1523static char *resolve_relative_path(const char *rel)
1524{
59556548 1525 if (!starts_with(rel, "./") && !starts_with(rel, "../"))
979f7929
NTND
1526 return NULL;
1527
979f7929
NTND
1528 if (!is_inside_work_tree())
1529 die("relative path syntax can't be used outside working tree.");
1530
1531 /* die() inside prefix_path() if resolved path is outside worktree */
1532 return prefix_path(startup_info->prefix,
1533 startup_info->prefix ? strlen(startup_info->prefix) : 0,
1534 rel);
1535}
1536
e82caf38 1537static int get_oid_with_context_1(const char *name,
1538 unsigned flags,
1539 const char *prefix,
1540 struct object_id *oid,
1541 struct object_context *oc)
a0cd87a5
MK
1542{
1543 int ret, bracket_depth;
73b0e5af
JH
1544 int namelen = strlen(name);
1545 const char *cp;
321c89bf 1546 int only_to_die = flags & GET_OID_ONLY_TO_DIE;
5119602a 1547
7243ffdd 1548 if (only_to_die)
321c89bf 1549 flags |= GET_OID_QUIETLY;
7243ffdd 1550
573285e5
CP
1551 memset(oc, 0, sizeof(*oc));
1552 oc->mode = S_IFINVALID;
d72cae12 1553 strbuf_init(&oc->symlink_path, 0);
e82caf38 1554 ret = get_oid_1(name, namelen, oid, flags);
73b0e5af
JH
1555 if (!ret)
1556 return ret;
33bd598c
JH
1557 /*
1558 * sha1:path --> object name of path in ent sha1
979f7929
NTND
1559 * :path -> object name of absolute path in index
1560 * :./path -> object name of path relative to cwd in index
73b0e5af 1561 * :[0-3]:path -> object name of path in index at stage
95ad6d2d 1562 * :/foo -> recent commit matching foo
73b0e5af
JH
1563 */
1564 if (name[0] == ':') {
1565 int stage = 0;
9c5e6c80 1566 const struct cache_entry *ce;
979f7929 1567 char *new_path = NULL;
73b0e5af 1568 int pos;
2e83b66c 1569 if (!only_to_die && namelen > 2 && name[1] == '/') {
84baa31b 1570 struct commit_list *list = NULL;
2b2a5be3 1571
84baa31b 1572 for_each_ref(handle_one_ref, &list);
e8d1dfe6 1573 commit_list_sort_by_date(&list);
e82caf38 1574 return get_oid_oneline(name + 2, oid, list);
84baa31b 1575 }
73b0e5af
JH
1576 if (namelen < 3 ||
1577 name[2] != ':' ||
1578 name[1] < '0' || '3' < name[1])
1579 cp = name + 1;
1580 else {
1581 stage = name[1] - '0';
1582 cp = name + 3;
5119602a 1583 }
3d6e0f74
JH
1584 new_path = resolve_relative_path(cp);
1585 if (!new_path) {
1586 namelen = namelen - (cp - name);
1587 } else {
1588 cp = new_path;
1589 namelen = strlen(cp);
1590 }
573285e5 1591
321c89bf 1592 if (flags & GET_OID_RECORD_PATH)
dc944b65 1593 oc->path = xstrdup(cp);
573285e5 1594
73b0e5af
JH
1595 if (!active_cache)
1596 read_cache();
73b0e5af
JH
1597 pos = cache_name_pos(cp, namelen);
1598 if (pos < 0)
1599 pos = -pos - 1;
1600 while (pos < active_nr) {
1601 ce = active_cache[pos];
1602 if (ce_namelen(ce) != namelen ||
1603 memcmp(ce->name, cp, namelen))
1604 break;
1605 if (ce_stage(ce) == stage) {
e82caf38 1606 oidcpy(oid, &ce->oid);
90064710 1607 oc->mode = ce->ce_mode;
979f7929 1608 free(new_path);
73b0e5af
JH
1609 return 0;
1610 }
e7cef45f 1611 pos++;
73b0e5af 1612 }
2e83b66c 1613 if (only_to_die && name[1] && name[1] != '/')
009fee47 1614 diagnose_invalid_index_path(stage, prefix, cp);
979f7929 1615 free(new_path);
73b0e5af
JH
1616 return -1;
1617 }
cce91a2c
SP
1618 for (cp = name, bracket_depth = 0; *cp; cp++) {
1619 if (*cp == '{')
1620 bracket_depth++;
1621 else if (bracket_depth && *cp == '}')
1622 bracket_depth--;
1623 else if (!bracket_depth && *cp == ':')
1624 break;
1625 }
1626 if (*cp == ':') {
e82caf38 1627 struct object_id tree_oid;
b2981d06 1628 int len = cp - name;
8a10fea4
JK
1629 unsigned sub_flags = flags;
1630
321c89bf 1631 sub_flags &= ~GET_OID_DISAMBIGUATORS;
1632 sub_flags |= GET_OID_TREEISH;
8a10fea4 1633
e82caf38 1634 if (!get_oid_1(name, len, &tree_oid, sub_flags)) {
009fee47 1635 const char *filename = cp+1;
979f7929
NTND
1636 char *new_filename = NULL;
1637
1638 new_filename = resolve_relative_path(filename);
1639 if (new_filename)
1640 filename = new_filename;
321c89bf 1641 if (flags & GET_OID_FOLLOW_SYMLINKS) {
e82caf38 1642 ret = get_tree_entry_follow_symlinks(tree_oid.hash,
1643 filename, oid->hash, &oc->symlink_path,
c4ec9677
DT
1644 &oc->mode);
1645 } else {
e82caf38 1646 ret = get_tree_entry(tree_oid.hash, filename,
1647 oid->hash, &oc->mode);
c4ec9677 1648 if (ret && only_to_die) {
e82caf38 1649 diagnose_invalid_oid_path(prefix,
c4ec9677 1650 filename,
e82caf38 1651 &tree_oid,
c4ec9677
DT
1652 name, len);
1653 }
009fee47 1654 }
e82caf38 1655 hashcpy(oc->tree, tree_oid.hash);
321c89bf 1656 if (flags & GET_OID_RECORD_PATH)
dc944b65 1657 oc->path = xstrdup(filename);
573285e5 1658
979f7929 1659 free(new_filename);
009fee47
MM
1660 return ret;
1661 } else {
2e83b66c 1662 if (only_to_die)
b2981d06 1663 die("Invalid object name '%.*s'.", len, name);
009fee47 1664 }
5119602a
LT
1665 }
1666 return ret;
9938af6a 1667}
f01cc14c 1668
8c135ea2
JH
1669/*
1670 * Call this function when you know "name" given by the end user must
1671 * name an object but it doesn't; the function _may_ die with a better
1672 * diagnostic message than "no such object 'name'", e.g. "Path 'doc' does not
1673 * exist in 'HEAD'" when given "HEAD:doc", or it may return in which case
1674 * you have a chance to diagnose the error further.
1675 */
1676void maybe_die_on_misspelt_object_name(const char *name, const char *prefix)
f01cc14c
JH
1677{
1678 struct object_context oc;
e82caf38 1679 struct object_id oid;
321c89bf 1680 get_oid_with_context_1(name, GET_OID_ONLY_TO_DIE, prefix, &oid, &oc);
8c135ea2
JH
1681}
1682
e82caf38 1683int get_oid_with_context(const char *str, unsigned flags, struct object_id *oid, struct object_context *oc)
f01cc14c 1684{
321c89bf 1685 if (flags & GET_OID_FOLLOW_SYMLINKS && flags & GET_OID_ONLY_TO_DIE)
c4ec9677 1686 die("BUG: incompatible flags for get_sha1_with_context");
e82caf38 1687 return get_oid_with_context_1(str, flags, NULL, oid, oc);
f01cc14c 1688}